Flight cancellations at Hamburg Airport after a surprise strike by workers have affected more than 40,000 passengers.

Other airports to be affected today include Frankfurt, Munich, Stuttgart, Cologne/Bonn, Duesseldorf, Dortmund, Hanover, Bremen, Berlin and Leipzig-Halle.

The airport in Germany’s second largest city said the one-day strike, called over pay and conditions, began earlier than expected “without any notice.”